Why Does My Air Conditioner Smell Bad?

Why Does My Air Conditioner Smell Bad?Four Reasons Your Air Conditioner Smells Bad

A strange, strong, or generally bad smell from your air conditioner is a sign something’s wrong. The scent could resemble gunpowder, urine, rotten eggs, or stale socks. Possibilities for it include:

  • Coolant Leaks
  • Mold or Mildew
  • Organic Waste
  • Electrical Issues

Each year, people rely more and more on their central air conditioners to keep them comfortable during the summer. And, this year, it may be even more essential.

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As we prepare to stay hunkered down as the weather gets warmer, we’ll want to be as comfortable as possible. Meanwhile, your cooling system can also help improve your indoor air quality.

When you have the windows closed, you rely on your AC to circulate the air in your house. Doing this helps get rid of allergens, pollutants, bacteria, and other contaminants that often build up in your home.

There’s no evidence that this filtration process affects the COVD-19 virus. But, the cooling system still plays an important role in your indoor air quality, especially for people with respiratory problems, to breathe easy when they’re at home.

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Air Conditioner Service and the COVD-19 Pandemic

Cipollone is available for air conditioner service, replacement, and maintenance during the pandemic. HVAC companies are considered essential in Pennsylvania.

We are taking every precaution to keep you, your family, and our staff safe and healthy.

All our techs currently wear booties and gloves when they come to your house. They’ll also wear facemasks if you prefer, and some wear them all the time anyway.

We wipe down any equipment we touch with Spray 9, which kills viruses. That includes door handles and the steering wheels in our trucks. And, we won’t touch your thermostat without gloves.

Although times are uncertain right now, things will certainly get better. In the meantime, we’re doing everything to make sure your home is comfortable, healthy, and safe this year.

Air Conditioner Smells Like Dirty Socks

That stale smell coming from your air conditioner has a name: Dirty sock syndrome. It’s a sign that there’s mold or bacteria somewhere in the system.

Air Conditioner Smells Like Dirty Socks

Technically, it’s the mycotoxins — a byproduct of mold — that you’re smelling. Either way, the scent resembles socks that you left in your gym bag for too long.

If you have a central air system, the odds are the problem is in the condenser. Mold is also a problem for ductless systems — it can grow in the air handlers.

You’ll need a professional to clean it out. Even if you’re able to see or access the problem, you don’t know if you’ve got it all. And, you risk damaging the equipment or hurting yourself.

And, if just the thought of this grosses you out, don’t worry: Regular preventative maintenance for ACs includes cleaning. If you get a tune-up every year — especially for mini splits — you won’t have this problem.

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Sulfur or Gunpowder Smell

Sulfur or a gunpowder smell from your air conditioner indicates a mechanical or electrical problem. Odds are, there’s some damaged wiring somewhere. Or, the motor us burned out or overheating.

Turn off your AC if you notice this smell. And, call a tech before turning it back on.

If there’s a problem such as this, you run the risk of damaging the equipment further if you keep running.

Urine Smell

If your air conditioner smells like urine or pee, you could be dealing with a few different problems. The main ones culprits are mold again, or a coolant leak.

Some people describe the scent as more like ammonia. But, either description can fit these bills.

It’s tough to do a visual inspection for mold, as we mentioned. You might get lucky (so to speak) and hear a hissing sound somewhere. That would clue you in about a leak.

But, it’s more likely the only indication you’ll have is that smell. So, you’ll need a professional.

And, in 2020, we need to talk a little more about coolant leaks.

R22 Refrigerant and AC Leaks

Up until ten years ago, air conditioners used R22, or freon, coolant. But, the EPA began phasing it out since it’s bad for the environment. As of this year, no companies manufacture it anymore.


That phaseout made R22 much harder to find. There’s still some out there, and recycled freon is available, too. But it’s becoming more expensive.

So, in many cases, we end up recommending replacing your unit when, previously, we may have been able to repair.

It’s a combination of the cost to repair along with the inflated price of R22 — if there’s any around.

If we catch a small leak early, it’s possible to recharge with a small amount of freon or recycled R22. But, we’re almost always recommending a new unit.

Now, you should also note this only applies to condensers more than a decade old. The refrigerant for newer models is widely available.

So, if you have an older unit, there’s a good chance it was coming up for replacement, anyway.

Air Conditioner Smells Like Rotten Eggs

A rotten egg smell from your air conditioner means an animal has crawled into the system somewhere — either in the outdoor condenser or somewhere in the ductwork. And it’s passed away.

Gross as it seems, that smell is from the decaying organic compounds.

So, catching a whiff like that coming through your vents is a sign something’s wrong. Once again, turn off the AC. You don’t want to circulate more bacteria, waste, or other pollutants throughout the house.

Call John Cipollone
Schedule An Appointment

Get Your Air Conditioner Tune-Up for Summer 2020

This year, it’s more important than ever to make sure our air conditioner is ready for the summer. The best way to do that is by scheduling a tune-up for the spring.

R22 Freon Phase Out: Does My Havertown, PA Home Need a New AC?

Read: 4 Benefits of Regular Maintenance

We don’t want to end things on a doom-and-gloom note. So, rather than just tell you all the things that can go wrong, we’ll also tell you how to prevent them from happening in the first place.

A tune-up falls under the topic of “preventative maintenance.” In other words, you’re having a professional come in and “fix” the system before there’s a problem.

With a tune-up, the tech cleans out the components, lubricates the moving parts, and inspects the entire system for any problems. They’ll also replace anything that’s worn down our already broken before they cause a malfunction.

We recommend these each year anyway. But, with people rightfully concerned with indoor air quality and trying to stay home as much as possible, it’s especially essential in 2020.

And, we’ll take every possible step to keep us all safe.

If you have any concerns about your cooling system or want to get it ready for the summer, call or email us today for an appointment.

Call John Cipollone
Schedule An Appointment

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